This invention relates to a towed submerged vehicle, and more particularly to the generation of forces acting on such vehicle in directions substantially normal to their direction of travel for purposes of depth and attitude control.
Heretofore, depth and attitude of submersible vehicles, notably those intended to be towed at predetermined depths for scientific or military purposes, has been achieved principally through the use of vanes, wings, canards and like control appendages. Such appendages are effective and can be varied in position, for example in response to water pressure, to maintian a selected depth in a towed vehicle. U.S. Pat. No. 3,749,045 to C. D. Angus, et al, presents good examples of such devices. Among the disadvantages inherent in the use of such control appendages are the notable size, weight, and cost factors, and in addition the very important factor of increased drag.
The factor of drag manifests itself in difficulties in keeping a high speed underwater towed vehicle at a desired water depth without placing exorbitant strains on the towing gear, as well as on towed device itself.
Vehicles having wings, diving planes, and the like are also prone to become unstable when operated at speeds for which turbulance and cavitation effects override designed lift or depressing forces. Moreover, control appendages increase likelihood of fouling on cables, underwater obstructions, and the like.